Simultaneous conversion of free fatty acids and triglycerides to biodiesel by immobilized Aspergillus oryzae expressing Fusarium heterosporum lipase

Abstract

The presence of high levels of free fatty acids (FFA) in oil is a barrier to one-step biodiesel production. Undesirable soaps are formed during conventional chemical methods, and enzyme deactivation occurs when enzymatic methods are used. This work investigates an efficient technique to simultaneously convert a mixture of free fatty acids and triglycerides (TAG). A partial soybean hydrolysate containing 73.04% free fatty acids and 24.81% triglycerides was used as a substrate for the enzymatic production of fatty acid methyl ester (FAME). Whole-cell Candida antarctica lipase B-expressing Aspergillus oryzae, and Novozym 435 produced only 75.2 and 73.5% FAME, respectively. Fusarium heterosporum lipase-expressing A. oryzae produced more than 93% FAME in 72 h using three molar equivalents of methanol. FFA and TAG were converted simultaneously in the presence of increasing water content that resulted from esterification. Therefore, F. heterosporum lipase with a noted high level of tolerance of water could be useful in the industrial production of biodiesel from feedstock that has high proportion of free fatty acids.

Concentration of Lipase from Aspergillus oryzae Expressing Fusarium heterosporum by Nanofiltration to Enhance Transesterification

“…The column was configured with an initial temperature of 130 • C for 2 min, which was raised to 350 • C at 10 • C/min, and then to 370 • C at 7 • C/min. The FAME composition in each reaction mixture was reported as the percentage of the oil in the reaction mixture using tricaprylin as an internal standard [11].…”

“…have been used to accomplish both transesterification and esterification [8][9][10]. Many researchers have attempted to solve the limitations of lipase-catalyzed biodiesel production by immobilizing the enzymes or cells on a suitable matrix [8,11] or via the use of a lipase cocktail [12]. In contrast, at least one previous study has successfully conducted biodiesel production using recombinant Aspergillus oryzae that expresses Fusarium heterosporum lipase (FHL), which has demonstrated a high level of tolerance to water [13].…”

Bioenergy and Biorefinery: Feedstock, Biotechnological Conversion, and Products

“…Candida antarctica lipase B (CALB), one of the most used lipases, is known to be nonspecific in its free state. CALB immobilized on polyurethane matrix, however, shows no activity towards triglycerides . Moreover, CALB immobilized on the hydrophobic acrylic resin (Novozym 435), one of the most extensively studied commercial lipase for biodiesel production, loses its transesterification activity in the presence of high amount of water .…”

“…CALB immobilized on polyurethane matrix, however, shows no activity towards triglycerides . Moreover, CALB immobilized on the hydrophobic acrylic resin (Novozym 435), one of the most extensively studied commercial lipase for biodiesel production, loses its transesterification activity in the presence of high amount of water . Table outlines some potential nonconventional feedstocks and techniques to improve their enzymatic conversion to biodiesel.…”

Oleochemicals from Palm Oil for the Petroleum Industry

“…However, the high FFA contents, solids and water impurities in waste vegetable oils will impact on the yield, product quality, and the economic feasibility of the process [63]. A relatively high FFA content in the feedstock will promote saponification of triglycerides forming by-products such as soap and water as illustrated in Figure 2 [64] .…”